diff --git a/compiler-rt/lib/tsan/CMakeLists.txt b/compiler-rt/lib/tsan/CMakeLists.txt
--- a/compiler-rt/lib/tsan/CMakeLists.txt
+++ b/compiler-rt/lib/tsan/CMakeLists.txt
@@ -114,6 +114,14 @@
 add_compiler_rt_component(tsan)
 
 if(APPLE)
+  # Ideally we would check the SDK version for the actual platform we are
+  # building for here.  To make our lifes easier we assume the host SDK setup is
+  # sane and use the macOS SDK version as a proxy for aligned SDKs.
+  find_darwin_sdk_version(macosx_sdk_version "macosx")
+  if ("${macosx_sdk_version}" VERSION_LESS 10.12)
+    message(FATAL_ERROR "Building the TSan runtime requires at least macOS SDK 10.12 (or aligned SDK on other platforms)")
+  endif()
+
   add_asm_sources(TSAN_ASM_SOURCES rtl/tsan_rtl_amd64.S rtl/tsan_rtl_aarch64.S)
 
   set(TSAN_LINK_LIBS ${SANITIZER_COMMON_LINK_LIBS})